Re: [PATCHv2 2/2] backlight: add TI LMU backlight driver

From: Daniel Thompson
Date: Thu Sep 07 2017 - 07:23:10 EST


On 17/07/17 14:39, Sebastian Reichel wrote:
From: Milo Kim <Milo.Kim@xxxxxx>

This is consolidated driver which supports the following
backlight devices: LM3532, LM3631, LM3632, LM3633, LM3695
and LM3697.

Structure
---------
It consists of two parts - core and data.

Core part supports features below.
- Backlight subsystem control
- Channel configuration from DT properties
- Light dimming effect control: ramp up and down.
- LMU fault monitor notifier handling
- PWM brightness control

Data part describes device specific data.
- Register value configuration for each LMU device
: initialization, channel configuration, control mode, enable and
brightness.
- PWM action configuration
- Light dimming effect table
- Option for LMU fault monitor support

Signed-off-by: Milo Kim <milo.kim@xxxxxx>
Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxxxx>

Is there a v3 pending?

I just found this patch near the bottom of my TODO list but IIRC I actually decided to defer final review of this driver until feedback on the bindings was resolved (and as a result I've just taken it off the TODO list).


Daniel.


---
drivers/video/backlight/Kconfig | 7 +
drivers/video/backlight/Makefile | 3 +
drivers/video/backlight/ti-lmu-backlight-core.c | 729 ++++++++++++++++++++++++
drivers/video/backlight/ti-lmu-backlight-data.c | 304 ++++++++++
drivers/video/backlight/ti-lmu-backlight-data.h | 95 +++
5 files changed, 1138 insertions(+)
create mode 100644 drivers/video/backlight/ti-lmu-backlight-core.c
create mode 100644 drivers/video/backlight/ti-lmu-backlight-data.c
create mode 100644 drivers/video/backlight/ti-lmu-backlight-data.h

diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 4e1d2ad50ba1..c3cc8334f9a2 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -427,6 +427,13 @@ config BACKLIGHT_SKY81452
To compile this driver as a module, choose M here: the module will
be called sky81452-backlight
+config BACKLIGHT_TI_LMU
+ tristate "Backlight driver for TI LMU"
+ depends on BACKLIGHT_CLASS_DEVICE && MFD_TI_LMU
+ help
+ Say Y to enable the backlight driver for TI LMU devices.
+ This supports LM3532, LM3631, LM3632, LM3633, LM3695 and LM3697.
+
config BACKLIGHT_TPS65217
tristate "TPS65217 Backlight"
depends on BACKLIGHT_CLASS_DEVICE && MFD_TPS65217
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index 8905129691e8..c532e43e344b 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -52,6 +52,9 @@ obj-$(CONFIG_BACKLIGHT_PM8941_WLED) += pm8941-wled.o
obj-$(CONFIG_BACKLIGHT_PWM) += pwm_bl.o
obj-$(CONFIG_BACKLIGHT_SAHARA) += kb3886_bl.o
obj-$(CONFIG_BACKLIGHT_SKY81452) += sky81452-backlight.o
+ti-lmu-backlight-objs := ti-lmu-backlight-core.o \
+ ti-lmu-backlight-data.o
+obj-$(CONFIG_BACKLIGHT_TI_LMU) += ti-lmu-backlight.o
obj-$(CONFIG_BACKLIGHT_TOSA) += tosa_bl.o
obj-$(CONFIG_BACKLIGHT_TPS65217) += tps65217_bl.o
obj-$(CONFIG_BACKLIGHT_WM831X) += wm831x_bl.o
diff --git a/drivers/video/backlight/ti-lmu-backlight-core.c b/drivers/video/backlight/ti-lmu-backlight-core.c
new file mode 100644
index 000000000000..fca95080ec27
--- /dev/null
+++ b/drivers/video/backlight/ti-lmu-backlight-core.c
@@ -0,0 +1,729 @@
+/*
+ * TI LMU (Lighting Management Unit) Backlight Driver
+ *
+ * Copyright 2015 Texas Instruments
+ *
+ * Author: Milo Kim <milo.kim@xxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/backlight.h>
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/mfd/ti-lmu.h>
+#include <linux/mfd/ti-lmu-register.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+
+#include "ti-lmu-backlight-data.h"
+
+enum ti_lmu_bl_ctrl_mode {
+ BL_REGISTER_BASED,
+ BL_PWM_BASED,
+};
+
+enum ti_lmu_bl_ramp_mode {
+ BL_RAMP_UP,
+ BL_RAMP_DOWN,
+};
+
+struct ti_lmu_bl;
+
+/**
+ * struct ti_lmu_bl_chip
+ *
+ * @dev: Parent device pointer
+ * @lmu: LMU structure.
+ * Used for register R/W access and notification.
+ * @cfg: Device configuration data
+ * @lmu_bl: Multiple backlight channels
+ * @num_backlights: Number of backlight channels
+ * @nb: Notifier block for handling LMU fault monitor event
+ *
+ * One backlight chip can have multiple backlight channels, 'ti_lmu_bl'.
+ */
+struct ti_lmu_bl_chip {
+ struct device *dev;
+ struct ti_lmu *lmu;
+ const struct ti_lmu_bl_cfg *cfg;
+ struct ti_lmu_bl *lmu_bl;
+ int num_backlights;
+ struct notifier_block nb;
+};
+
+/**
+ * struct ti_lmu_bl
+ *
+ * @chip: Pointer to parent backlight device
+ * @bl_dev: Backlight subsystem device structure
+ * @bank_id: Backlight bank ID
+ * @name: Backlight channel name
+ * @mode: Backlight control mode
+ * @led_sources: Backlight output channel configuration.
+ * Bit mask is set on parsing DT.
+ * @default_brightness: [Optional] Initial brightness value
+ * @ramp_up_msec: [Optional] Ramp up time
+ * @ramp_down_msec: [Optional] Ramp down time
+ * @pwm_period: [Optional] PWM period
+ * @pwm: [Optional] PWM subsystem structure
+ *
+ * Each backlight device has its own channel configuration.
+ * For chip control, parent chip data structure is used.
+ */
+struct ti_lmu_bl {
+ struct ti_lmu_bl_chip *chip;
+ struct backlight_device *bl_dev;
+
+ int bank_id;
+ const char *name;
+ enum ti_lmu_bl_ctrl_mode mode;
+ unsigned long led_sources;
+
+ unsigned int default_brightness;
+
+ /* Used for lighting effect */
+ unsigned int ramp_up_msec;
+ unsigned int ramp_down_msec;
+
+ /* Only valid in PWM mode */
+ unsigned int pwm_period;
+ struct pwm_device *pwm;
+};
+
+#define NUM_DUAL_CHANNEL 2
+#define LMU_BACKLIGHT_DUAL_CHANNEL_USED (BIT(0) | BIT(1))
+#define LMU_BACKLIGHT_11BIT_LSB_MASK (BIT(0) | BIT(1) | BIT(2))
+#define LMU_BACKLIGHT_11BIT_MSB_SHIFT 3
+#define DEFAULT_PWM_NAME "lmu-backlight"
+
+static int ti_lmu_backlight_enable(struct ti_lmu_bl *lmu_bl, bool enable)
+{
+ struct ti_lmu_bl_chip *chip = lmu_bl->chip;
+ struct regmap *regmap = chip->lmu->regmap;
+ unsigned long enable_time = chip->cfg->reginfo->enable_usec;
+ u8 *reg = chip->cfg->reginfo->enable;
+ u8 mask = BIT(lmu_bl->bank_id);
+ u8 val = (enable == true) ? mask : 0;
+ int ret;
+
+ if (!reg)
+ return -EINVAL;
+
+ ret = regmap_update_bits(regmap, *reg, mask, val);
+ if (ret)
+ return ret;
+
+ if (enable_time > 0)
+ usleep_range(enable_time, enable_time + 100);
+
+ return 0;
+}
+
+static int ti_lmu_backlight_pwm_ctrl(struct ti_lmu_bl *lmu_bl, int brightness,
+ int max_brightness)
+{
+ struct pwm_state state = { };
+ int ret;
+
+ if (!lmu_bl->pwm) {
+ lmu_bl->pwm = devm_pwm_get(lmu_bl->chip->dev, DEFAULT_PWM_NAME);
+ if (IS_ERR(lmu_bl->pwm)) {
+ ret = PTR_ERR(lmu_bl->pwm);
+ lmu_bl->pwm = NULL;
+ dev_err(lmu_bl->chip->dev,
+ "Can not get PWM device, err: %d\n", ret);
+ return ret;
+ }
+ }
+
+ pwm_init_state(lmu_bl->pwm, &state);
+ state.period = lmu_bl->pwm_period;
+ state.duty_cycle = brightness * state.period / max_brightness;
+
+ if (state.duty_cycle)
+ state.enabled = true;
+ else
+ state.enabled = false;
+
+ ret = pwm_apply_state(lmu_bl->pwm, &state);
+ if (ret)
+ dev_err(lmu_bl->chip->dev, "Failed to configure PWM: %d", ret);
+
+ return ret;
+}
+
+static int ti_lmu_backlight_update_brightness_register(struct ti_lmu_bl *lmu_bl,
+ int brightness)
+{
+ const struct ti_lmu_bl_cfg *cfg = lmu_bl->chip->cfg;
+ const struct ti_lmu_bl_reg *reginfo = cfg->reginfo;
+ struct regmap *regmap = lmu_bl->chip->lmu->regmap;
+ u8 reg, val;
+ int ret;
+
+ /*
+ * Brightness register update
+ *
+ * 11 bit dimming: update LSB bits and write MSB byte.
+ * MSB brightness should be shifted.
+ * 8 bit dimming: write MSB byte.
+ */
+ if (cfg->max_brightness == MAX_BRIGHTNESS_11BIT) {
+ reg = reginfo->brightness_lsb[lmu_bl->bank_id];
+ ret = regmap_update_bits(regmap, reg,
+ LMU_BACKLIGHT_11BIT_LSB_MASK,
+ brightness);
+ if (ret)
+ return ret;
+
+ val = brightness >> LMU_BACKLIGHT_11BIT_MSB_SHIFT;
+ } else {
+ val = brightness;
+ }
+
+ reg = reginfo->brightness_msb[lmu_bl->bank_id];
+ return regmap_write(regmap, reg, val);
+}
+
+static int ti_lmu_backlight_update_status(struct backlight_device *bl_dev)
+{
+ struct ti_lmu_bl *lmu_bl = bl_get_data(bl_dev);
+ const struct ti_lmu_bl_cfg *cfg = lmu_bl->chip->cfg;
+ int brightness = bl_dev->props.brightness;
+ bool enable = brightness > 0;
+ int ret;
+
+ if (bl_dev->props.state & BL_CORE_SUSPENDED)
+ brightness = 0;
+
+ ret = ti_lmu_backlight_enable(lmu_bl, enable);
+ if (ret)
+ return ret;
+
+ if (lmu_bl->mode == BL_PWM_BASED) {
+ ti_lmu_backlight_pwm_ctrl(lmu_bl, brightness,
+ bl_dev->props.max_brightness);
+
+ switch (cfg->pwm_action) {
+ case UPDATE_PWM_ONLY:
+ /* No register update is required */
+ return 0;
+ case UPDATE_MAX_BRT:
+ /*
+ * PWM can start from any non-zero code and dim down
+ * to zero. So, brightness register should be updated
+ * even in PWM mode.
+ */
+ if (brightness > 0)
+ brightness = MAX_BRIGHTNESS_11BIT;
+ else
+ brightness = 0;
+ break;
+ default:
+ break;
+ }
+ }
+
+ return ti_lmu_backlight_update_brightness_register(lmu_bl, brightness);
+}
+
+static const struct backlight_ops lmu_backlight_ops = {
+ .options = BL_CORE_SUSPENDRESUME,
+ .update_status = ti_lmu_backlight_update_status,
+};
+
+static int ti_lmu_backlight_of_get_ctrl_bank(struct device_node *np,
+ struct ti_lmu_bl *lmu_bl)
+{
+ const char *name;
+ u32 *sources;
+ int num_channels = lmu_bl->chip->cfg->num_channels;
+ int ret, num_sources;
+
+ sources = devm_kzalloc(lmu_bl->chip->dev, num_channels, GFP_KERNEL);
+ if (!sources)
+ return -ENOMEM;
+
+ if (!of_property_read_string(np, "label", &name))
+ lmu_bl->name = name;
+ else
+ lmu_bl->name = np->name;
+
+ ret = of_property_count_u32_elems(np, "led-sources");
+ if (ret < 0 || ret > num_channels)
+ return -EINVAL;
+
+ num_sources = ret;
+ ret = of_property_read_u32_array(np, "led-sources", sources,
+ num_sources);
+ if (ret)
+ return ret;
+
+ lmu_bl->led_sources = 0;
+ while (num_sources--)
+ set_bit(sources[num_sources], &lmu_bl->led_sources);
+
+ return 0;
+}
+
+static void ti_lmu_backlight_of_get_light_properties(struct device_node *np,
+ struct ti_lmu_bl *lmu_bl)
+{
+ of_property_read_u32(np, "default-brightness-level",
+ &lmu_bl->default_brightness);
+
+ of_property_read_u32(np, "ramp-up-msec", &lmu_bl->ramp_up_msec);
+ of_property_read_u32(np, "ramp-down-msec", &lmu_bl->ramp_down_msec);
+}
+
+static void ti_lmu_backlight_of_get_brightness_mode(struct device_node *np,
+ struct ti_lmu_bl *lmu_bl)
+{
+ of_property_read_u32(np, "pwm-period", &lmu_bl->pwm_period);
+
+ if (lmu_bl->pwm_period > 0)
+ lmu_bl->mode = BL_PWM_BASED;
+ else
+ lmu_bl->mode = BL_REGISTER_BASED;
+}
+
+static int ti_lmu_backlight_of_create(struct ti_lmu_bl_chip *chip,
+ struct device_node *np)
+{
+ struct device_node *child;
+ struct ti_lmu_bl *lmu_bl, *each;
+ int ret, num_backlights;
+ int i = 0;
+
+ num_backlights = of_get_child_count(np);
+ if (num_backlights == 0) {
+ dev_err(chip->dev, "No backlight strings\n");
+ return -ENODEV;
+ }
+
+ /* One chip can have mulitple backlight strings */
+ lmu_bl = devm_kzalloc(chip->dev, sizeof(*lmu_bl) * num_backlights,
+ GFP_KERNEL);
+ if (!lmu_bl)
+ return -ENOMEM;
+
+ /* Child is mapped to LMU backlight control bank */
+ for_each_child_of_node(np, child) {
+ each = lmu_bl + i;
+ each->bank_id = i;
+ each->chip = chip;
+
+ ret = ti_lmu_backlight_of_get_ctrl_bank(child, each);
+ if (ret) {
+ of_node_put(np);
+ return ret;
+ }
+
+ ti_lmu_backlight_of_get_light_properties(child, each);
+ ti_lmu_backlight_of_get_brightness_mode(child, each);
+
+ i++;
+ }
+
+ chip->lmu_bl = lmu_bl;
+ chip->num_backlights = num_backlights;
+
+ return 0;
+}
+
+static int ti_lmu_backlight_check_channel(struct ti_lmu_bl *lmu_bl)
+{
+ const struct ti_lmu_bl_cfg *cfg = lmu_bl->chip->cfg;
+ const struct ti_lmu_bl_reg *reginfo = lmu_bl->chip->cfg->reginfo;
+
+ if (!reginfo->brightness_msb)
+ return -EINVAL;
+
+ if (cfg->max_brightness > MAX_BRIGHTNESS_8BIT) {
+ if (!reginfo->brightness_lsb)
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ti_lmu_backlight_create_channel(struct ti_lmu_bl *lmu_bl)
+{
+ struct regmap *regmap = lmu_bl->chip->lmu->regmap;
+ const struct lmu_bl_reg_data *regdata =
+ lmu_bl->chip->cfg->reginfo->channel;
+ int num_channels = lmu_bl->chip->cfg->num_channels;
+ int i, ret;
+ u8 shift;
+
+ /*
+ * How to create backlight output channels:
+ * Check 'led_sources' bit and update registers.
+ *
+ * 1) Dual channel configuration
+ * The 1st register data is used for single channel.
+ * The 2nd register data is used for dual channel.
+ *
+ * 2) Multiple channel configuration
+ * Each register data is mapped to bank ID.
+ * Bit shift operation is defined in channel registers.
+ *
+ * Channel register data consists of address, mask, value.
+ */
+
+ if (num_channels == NUM_DUAL_CHANNEL) {
+ if (lmu_bl->led_sources == LMU_BACKLIGHT_DUAL_CHANNEL_USED)
+ regdata++;
+
+ return regmap_update_bits(regmap, regdata->reg, regdata->mask,
+ regdata->val);
+ }
+
+ for (i = 0; regdata && i < num_channels; i++) {
+ /*
+ * Note that the result of regdata->val is shift bit.
+ * The bank_id should be shifted for the channel configuration.
+ */
+ if (test_bit(i, &lmu_bl->led_sources)) {
+ shift = regdata->val;
+ ret = regmap_update_bits(regmap, regdata->reg,
+ regdata->mask,
+ lmu_bl->bank_id << shift);
+ if (ret)
+ return ret;
+ }
+
+ regdata++;
+ }
+
+ return 0;
+}
+
+static int ti_lmu_backlight_update_ctrl_mode(struct ti_lmu_bl *lmu_bl)
+{
+ struct regmap *regmap = lmu_bl->chip->lmu->regmap;
+ const struct lmu_bl_reg_data *regdata =
+ lmu_bl->chip->cfg->reginfo->mode + lmu_bl->bank_id;
+ u8 val = regdata->val;
+
+ if (!regdata)
+ return 0;
+
+ /*
+ * Update PWM configuration register.
+ * If the mode is register based, then clear the bit.
+ */
+ if (lmu_bl->mode != BL_PWM_BASED)
+ val = 0;
+
+ return regmap_update_bits(regmap, regdata->reg, regdata->mask, val);
+}
+
+static int ti_lmu_backlight_convert_ramp_to_index(struct ti_lmu_bl *lmu_bl,
+ enum ti_lmu_bl_ramp_mode mode)
+{
+ const int *ramp_table = lmu_bl->chip->cfg->ramp_table;
+ const int size = lmu_bl->chip->cfg->size_ramp;
+ unsigned int msec;
+ int i;
+
+ if (!ramp_table)
+ return -EINVAL;
+
+ switch (mode) {
+ case BL_RAMP_UP:
+ msec = lmu_bl->ramp_up_msec;
+ break;
+ case BL_RAMP_DOWN:
+ msec = lmu_bl->ramp_down_msec;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (msec <= ramp_table[0])
+ return 0;
+
+ if (msec > ramp_table[size - 1])
+ return size - 1;
+
+ for (i = 1; i < size; i++) {
+ if (msec == ramp_table[i])
+ return i;
+
+ /* Find an approximate index by looking up the table */
+ if (msec > ramp_table[i - 1] && msec < ramp_table[i]) {
+ if (msec - ramp_table[i - 1] < ramp_table[i] - msec)
+ return i - 1;
+ else
+ return i;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static int ti_lmu_backlight_set_ramp(struct ti_lmu_bl *lmu_bl)
+{
+ struct regmap *regmap = lmu_bl->chip->lmu->regmap;
+ const struct ti_lmu_bl_reg *reginfo = lmu_bl->chip->cfg->reginfo;
+ int offset = reginfo->ramp_reg_offset;
+ int i, ret, index;
+ struct lmu_bl_reg_data regdata;
+
+ for (i = BL_RAMP_UP; i <= BL_RAMP_DOWN; i++) {
+ index = ti_lmu_backlight_convert_ramp_to_index(lmu_bl, i);
+ if (index > 0) {
+ if (!reginfo->ramp)
+ break;
+
+ regdata = reginfo->ramp[i];
+ if (lmu_bl->bank_id != 0)
+ regdata.val += offset;
+
+ /* regdata.val is shift bit */
+ ret = regmap_update_bits(regmap, regdata.reg,
+ regdata.mask,
+ index << regdata.val);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int ti_lmu_backlight_configure(struct ti_lmu_bl *lmu_bl)
+{
+ int ret;
+
+ ret = ti_lmu_backlight_check_channel(lmu_bl);
+ if (ret)
+ return ret;
+
+ ret = ti_lmu_backlight_create_channel(lmu_bl);
+ if (ret)
+ return ret;
+
+ ret = ti_lmu_backlight_update_ctrl_mode(lmu_bl);
+ if (ret)
+ return ret;
+
+ return ti_lmu_backlight_set_ramp(lmu_bl);
+}
+
+static int ti_lmu_backlight_init(struct ti_lmu_bl_chip *chip)
+{
+ struct regmap *regmap = chip->lmu->regmap;
+ const struct lmu_bl_reg_data *regdata =
+ chip->cfg->reginfo->init;
+ int num_init = chip->cfg->reginfo->num_init;
+ int i, ret;
+
+ for (i = 0; regdata && i < num_init; i++) {
+ ret = regmap_update_bits(regmap, regdata->reg, regdata->mask,
+ regdata->val);
+ if (ret)
+ return ret;
+
+ regdata++;
+ }
+
+ return 0;
+}
+
+static int ti_lmu_backlight_reload(struct ti_lmu_bl_chip *chip)
+{
+ struct ti_lmu_bl *each;
+ int i, ret;
+
+ ret = ti_lmu_backlight_init(chip);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < chip->num_backlights; i++) {
+ each = chip->lmu_bl + i;
+ ret = ti_lmu_backlight_configure(each);
+ if (ret)
+ return ret;
+
+ ret = backlight_update_status(each->bl_dev);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int ti_lmu_backlight_add_device(struct device *dev,
+ struct ti_lmu_bl *lmu_bl)
+{
+ struct backlight_device *bl_dev;
+ struct backlight_properties props;
+
+ memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
+ props.brightness = lmu_bl->default_brightness;
+ props.max_brightness = lmu_bl->chip->cfg->max_brightness;
+
+ bl_dev = devm_backlight_device_register(dev, lmu_bl->name,
+ lmu_bl->chip->dev, lmu_bl,
+ &lmu_backlight_ops, &props);
+ if (IS_ERR(bl_dev))
+ return PTR_ERR(bl_dev);
+
+ lmu_bl->bl_dev = bl_dev;
+
+ return 0;
+}
+
+static struct ti_lmu_bl_chip *
+ti_lmu_backlight_register(struct device *dev, struct ti_lmu *lmu,
+ const struct ti_lmu_bl_cfg *cfg)
+{
+ struct ti_lmu_bl_chip *chip;
+ struct ti_lmu_bl *each;
+ int i, ret;
+
+ if (!cfg) {
+ dev_err(dev, "Operation is not configured\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return ERR_PTR(-ENOMEM);
+
+ chip->dev = dev;
+ chip->lmu = lmu;
+ chip->cfg = cfg;
+
+ ret = ti_lmu_backlight_of_create(chip, dev->of_node);
+ if (ret)
+ return ERR_PTR(ret);
+
+ ret = ti_lmu_backlight_init(chip);
+ if (ret) {
+ dev_err(dev, "Backlight init err: %d\n", ret);
+ return ERR_PTR(ret);
+ }
+
+ for (i = 0; i < chip->num_backlights; i++) {
+ each = chip->lmu_bl + i;
+
+ ret = ti_lmu_backlight_configure(each);
+ if (ret) {
+ dev_err(dev, "Backlight config err: %d\n", ret);
+ return ERR_PTR(ret);
+ }
+
+ ret = ti_lmu_backlight_add_device(dev, each);
+ if (ret) {
+ dev_err(dev, "Backlight device err: %d\n", ret);
+ return ERR_PTR(ret);
+ }
+
+ ret = backlight_update_status(each->bl_dev);
+ if (ret) {
+ dev_err(dev, "Backlight update err: %d\n", ret);
+ return ERR_PTR(ret);
+ }
+ }
+
+ return chip;
+}
+
+static void ti_lmu_backlight_unregister(struct ti_lmu_bl_chip *chip)
+{
+ struct ti_lmu_bl *each;
+ int i;
+
+ /* Turn off the brightness */
+ for (i = 0; i < chip->num_backlights; i++) {
+ each = chip->lmu_bl + i;
+ each->bl_dev->props.brightness = 0;
+ backlight_update_status(each->bl_dev);
+ }
+}
+
+static int ti_lmu_backlight_monitor_notifier(struct notifier_block *nb,
+ unsigned long action, void *unused)
+{
+ struct ti_lmu_bl_chip *chip = container_of(nb, struct ti_lmu_bl_chip,
+ nb);
+
+ if (action == LMU_EVENT_MONITOR_DONE) {
+ if (ti_lmu_backlight_reload(chip))
+ return NOTIFY_STOP;
+ }
+
+ return NOTIFY_OK;
+}
+
+static int ti_lmu_backlight_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ti_lmu *lmu = dev_get_drvdata(dev->parent);
+ struct ti_lmu_bl_chip *chip;
+ int ret;
+
+ chip = ti_lmu_backlight_register(dev, lmu, &lmu_bl_cfg[pdev->id]);
+ if (IS_ERR(chip))
+ return PTR_ERR(chip);
+
+ /*
+ * Notifier callback is required because backlight device needs
+ * reconfiguration after fault detection procedure is done by
+ * ti-lmu-fault-monitor driver.
+ */
+ if (chip->cfg->fault_monitor_used) {
+ chip->nb.notifier_call = ti_lmu_backlight_monitor_notifier;
+ ret = blocking_notifier_chain_register(&chip->lmu->notifier,
+ &chip->nb);
+ if (ret)
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, chip);
+
+ return 0;
+}
+
+static int ti_lmu_backlight_remove(struct platform_device *pdev)
+{
+ struct ti_lmu_bl_chip *chip = platform_get_drvdata(pdev);
+
+ if (chip->cfg->fault_monitor_used)
+ blocking_notifier_chain_unregister(&chip->lmu->notifier,
+ &chip->nb);
+
+ ti_lmu_backlight_unregister(chip);
+
+ return 0;
+}
+
+static struct platform_driver ti_lmu_backlight_driver = {
+ .probe = ti_lmu_backlight_probe,
+ .remove = ti_lmu_backlight_remove,
+ .driver = {
+ .name = "ti-lmu-backlight",
+ },
+};
+
+module_platform_driver(ti_lmu_backlight_driver)
+
+MODULE_DESCRIPTION("TI LMU Backlight Driver");
+MODULE_AUTHOR("Milo Kim");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:ti-lmu-backlight");
diff --git a/drivers/video/backlight/ti-lmu-backlight-data.c b/drivers/video/backlight/ti-lmu-backlight-data.c
new file mode 100644
index 000000000000..583136cb934d
--- /dev/null
+++ b/drivers/video/backlight/ti-lmu-backlight-data.c
@@ -0,0 +1,304 @@
+/*
+ * TI LMU (Lighting Management Unit) Backlight Device Data
+ *
+ * Copyright 2015 Texas Instruments
+ *
+ * Author: Milo Kim <milo.kim@xxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "ti-lmu-backlight-data.h"
+
+/* LM3532 */
+static const struct lmu_bl_reg_data lm3532_init_data[] = {
+ { LM3532_REG_ZONE_CFG_A, LM3532_ZONE_MASK, LM3532_ZONE_0 },
+ { LM3532_REG_ZONE_CFG_B, LM3532_ZONE_MASK, LM3532_ZONE_1 },
+ { LM3532_REG_ZONE_CFG_C, LM3532_ZONE_MASK, LM3532_ZONE_2 },
+};
+
+static const struct lmu_bl_reg_data lm3532_channel_data[] = {
+ { LM3532_REG_OUTPUT_CFG, LM3532_ILED1_CFG_MASK,
+ LM3532_ILED1_CFG_SHIFT },
+ { LM3532_REG_OUTPUT_CFG, LM3532_ILED2_CFG_MASK,
+ LM3532_ILED2_CFG_SHIFT },
+ { LM3532_REG_OUTPUT_CFG, LM3532_ILED3_CFG_MASK,
+ LM3532_ILED3_CFG_SHIFT },
+};
+
+static const struct lmu_bl_reg_data lm3532_mode_data[] = {
+ { LM3532_REG_PWM_A_CFG, LM3532_PWM_A_MASK, LM3532_PWM_ZONE_0 },
+ { LM3532_REG_PWM_B_CFG, LM3532_PWM_B_MASK, LM3532_PWM_ZONE_1 },
+ { LM3532_REG_PWM_C_CFG, LM3532_PWM_C_MASK, LM3532_PWM_ZONE_2 },
+};
+
+static const struct lmu_bl_reg_data lm3532_ramp_data[] = {
+ { LM3532_REG_RAMPUP, LM3532_RAMPUP_MASK, LM3532_RAMPUP_SHIFT },
+ { LM3532_REG_RAMPDN, LM3532_RAMPDN_MASK, LM3532_RAMPDN_SHIFT },
+};
+
+static u8 lm3532_enable_reg = LM3532_REG_ENABLE;
+
+static u8 lm3532_brightness_regs[] = {
+ LM3532_REG_BRT_A,
+ LM3532_REG_BRT_B,
+ LM3532_REG_BRT_C,
+};
+
+static const struct ti_lmu_bl_reg lm3532_reg_info = {
+ .init = lm3532_init_data,
+ .num_init = ARRAY_SIZE(lm3532_init_data),
+ .channel = lm3532_channel_data,
+ .mode = lm3532_mode_data,
+ .ramp = lm3532_ramp_data,
+ .enable = &lm3532_enable_reg,
+ .brightness_msb = lm3532_brightness_regs,
+};
+
+/* LM3631 */
+static const struct lmu_bl_reg_data lm3631_init_data[] = {
+ { LM3631_REG_BRT_MODE, LM3631_MODE_MASK, LM3631_DEFAULT_MODE },
+ { LM3631_REG_BL_CFG, LM3631_MAP_MASK, LM3631_EXPONENTIAL_MAP },
+};
+
+static const struct lmu_bl_reg_data lm3631_channel_data[] = {
+ { LM3631_REG_BL_CFG, LM3631_BL_CHANNEL_MASK, LM3631_BL_SINGLE_CHANNEL },
+ { LM3631_REG_BL_CFG, LM3631_BL_CHANNEL_MASK, LM3631_BL_DUAL_CHANNEL },
+};
+
+static const struct lmu_bl_reg_data lm3631_ramp_data[] = {
+ { LM3631_REG_SLOPE, LM3631_SLOPE_MASK, LM3631_SLOPE_SHIFT },
+};
+
+static u8 lm3631_enable_reg = LM3631_REG_DEVCTRL;
+static u8 lm3631_brightness_msb_reg = LM3631_REG_BRT_MSB;
+static u8 lm3631_brightness_lsb_reg = LM3631_REG_BRT_LSB;
+
+static const struct ti_lmu_bl_reg lm3631_reg_info = {
+ .init = lm3631_init_data,
+ .num_init = ARRAY_SIZE(lm3631_init_data),
+ .channel = lm3631_channel_data,
+ .ramp = lm3631_ramp_data,
+ .enable = &lm3631_enable_reg,
+ .brightness_msb = &lm3631_brightness_msb_reg,
+ .brightness_lsb = &lm3631_brightness_lsb_reg,
+};
+
+/* LM3632 */
+static const struct lmu_bl_reg_data lm3632_init_data[] = {
+ { LM3632_REG_CONFIG1, LM3632_OVP_MASK, LM3632_OVP_25V },
+ { LM3632_REG_CONFIG2, LM3632_SWFREQ_MASK, LM3632_SWFREQ_1MHZ },
+};
+
+static const struct lmu_bl_reg_data lm3632_channel_data[] = {
+ { LM3632_REG_ENABLE, LM3632_BL_CHANNEL_MASK, LM3632_BL_SINGLE_CHANNEL },
+ { LM3632_REG_ENABLE, LM3632_BL_CHANNEL_MASK, LM3632_BL_DUAL_CHANNEL },
+};
+
+static const struct lmu_bl_reg_data lm3632_mode_data[] = {
+ { LM3632_REG_IO_CTRL, LM3632_PWM_MASK, LM3632_PWM_MODE },
+};
+
+static u8 lm3632_enable_reg = LM3632_REG_ENABLE;
+static u8 lm3632_brightness_msb_reg = LM3632_REG_BRT_MSB;
+static u8 lm3632_brightness_lsb_reg = LM3632_REG_BRT_LSB;
+
+static const struct ti_lmu_bl_reg lm3632_reg_info = {
+ .init = lm3632_init_data,
+ .num_init = ARRAY_SIZE(lm3632_init_data),
+ .channel = lm3632_channel_data,
+ .mode = lm3632_mode_data,
+ .enable = &lm3632_enable_reg,
+ .brightness_msb = &lm3632_brightness_msb_reg,
+ .brightness_lsb = &lm3632_brightness_lsb_reg,
+};
+
+/* LM3633 */
+static const struct lmu_bl_reg_data lm3633_init_data[] = {
+ { LM3633_REG_BOOST_CFG, LM3633_OVP_MASK, LM3633_OVP_40V },
+ { LM3633_REG_BL_RAMP_CONF, LM3633_BL_RAMP_MASK, LM3633_BL_RAMP_EACH },
+};
+
+static const struct lmu_bl_reg_data lm3633_channel_data[] = {
+ { LM3633_REG_HVLED_OUTPUT_CFG, LM3633_HVLED1_CFG_MASK,
+ LM3633_HVLED1_CFG_SHIFT },
+ { LM3633_REG_HVLED_OUTPUT_CFG, LM3633_HVLED2_CFG_MASK,
+ LM3633_HVLED2_CFG_SHIFT },
+ { LM3633_REG_HVLED_OUTPUT_CFG, LM3633_HVLED3_CFG_MASK,
+ LM3633_HVLED3_CFG_SHIFT },
+};
+
+static const struct lmu_bl_reg_data lm3633_mode_data[] = {
+ { LM3633_REG_PWM_CFG, LM3633_PWM_A_MASK, LM3633_PWM_A_MASK },
+ { LM3633_REG_PWM_CFG, LM3633_PWM_B_MASK, LM3633_PWM_B_MASK },
+};
+
+static const struct lmu_bl_reg_data lm3633_ramp_data[] = {
+ { LM3633_REG_BL0_RAMP, LM3633_BL_RAMPUP_MASK, LM3633_BL_RAMPUP_SHIFT },
+ { LM3633_REG_BL0_RAMP, LM3633_BL_RAMPDN_MASK, LM3633_BL_RAMPDN_SHIFT },
+};
+
+static u8 lm3633_enable_reg = LM3633_REG_ENABLE;
+
+static u8 lm3633_brightness_msb_regs[] = {
+ LM3633_REG_BRT_HVLED_A_MSB,
+ LM3633_REG_BRT_HVLED_B_MSB,
+};
+
+static u8 lm3633_brightness_lsb_regs[] = {
+ LM3633_REG_BRT_HVLED_A_LSB,
+ LM3633_REG_BRT_HVLED_B_LSB,
+};
+
+static const struct ti_lmu_bl_reg lm3633_reg_info = {
+ .init = lm3633_init_data,
+ .num_init = ARRAY_SIZE(lm3633_init_data),
+ .channel = lm3633_channel_data,
+ .mode = lm3633_mode_data,
+ .ramp = lm3633_ramp_data,
+ .ramp_reg_offset = 1, /* For LM3633_REG_BL1_RAMPUP/DN */
+ .enable = &lm3633_enable_reg,
+ .brightness_msb = lm3633_brightness_msb_regs,
+ .brightness_lsb = lm3633_brightness_lsb_regs,
+};
+
+/* LM3695 */
+static const struct lmu_bl_reg_data lm3695_init_data[] = {
+ { LM3695_REG_GP, LM3695_BRT_RW_MASK, LM3695_BRT_RW_MASK },
+};
+
+static const struct lmu_bl_reg_data lm3695_channel_data[] = {
+ { LM3695_REG_GP, LM3695_BL_CHANNEL_MASK, LM3695_BL_SINGLE_CHANNEL },
+ { LM3695_REG_GP, LM3695_BL_CHANNEL_MASK, LM3695_BL_DUAL_CHANNEL },
+};
+
+static u8 lm3695_enable_reg = LM3695_REG_GP;
+static u8 lm3695_brightness_msb_reg = LM3695_REG_BRT_MSB;
+static u8 lm3695_brightness_lsb_reg = LM3695_REG_BRT_LSB;
+
+static const struct ti_lmu_bl_reg lm3695_reg_info = {
+ .init = lm3695_init_data,
+ .num_init = ARRAY_SIZE(lm3695_init_data),
+ .channel = lm3695_channel_data,
+ .enable = &lm3695_enable_reg,
+ .enable_usec = 600,
+ .brightness_msb = &lm3695_brightness_msb_reg,
+ .brightness_lsb = &lm3695_brightness_lsb_reg,
+};
+
+/* LM3697 */
+static const struct lmu_bl_reg_data lm3697_init_data[] = {
+ { LM3697_REG_RAMP_CONF, LM3697_RAMP_MASK, LM3697_RAMP_EACH },
+};
+
+static const struct lmu_bl_reg_data lm3697_channel_data[] = {
+ { LM3697_REG_HVLED_OUTPUT_CFG, LM3697_HVLED1_CFG_MASK,
+ LM3697_HVLED1_CFG_SHIFT },
+ { LM3697_REG_HVLED_OUTPUT_CFG, LM3697_HVLED2_CFG_MASK,
+ LM3697_HVLED2_CFG_SHIFT },
+ { LM3697_REG_HVLED_OUTPUT_CFG, LM3697_HVLED3_CFG_MASK,
+ LM3697_HVLED3_CFG_SHIFT },
+};
+
+static const struct lmu_bl_reg_data lm3697_mode_data[] = {
+ { LM3697_REG_PWM_CFG, LM3697_PWM_A_MASK, LM3697_PWM_A_MASK },
+ { LM3697_REG_PWM_CFG, LM3697_PWM_B_MASK, LM3697_PWM_B_MASK },
+};
+
+static const struct lmu_bl_reg_data lm3697_ramp_data[] = {
+ { LM3697_REG_BL0_RAMP, LM3697_RAMPUP_MASK, LM3697_RAMPUP_SHIFT },
+ { LM3697_REG_BL0_RAMP, LM3697_RAMPDN_MASK, LM3697_RAMPDN_SHIFT },
+};
+
+static u8 lm3697_enable_reg = LM3697_REG_ENABLE;
+
+static u8 lm3697_brightness_msb_regs[] = {
+ LM3697_REG_BRT_A_MSB,
+ LM3697_REG_BRT_B_MSB,
+};
+
+static u8 lm3697_brightness_lsb_regs[] = {
+ LM3697_REG_BRT_A_LSB,
+ LM3697_REG_BRT_B_LSB,
+};
+
+static const struct ti_lmu_bl_reg lm3697_reg_info = {
+ .init = lm3697_init_data,
+ .num_init = ARRAY_SIZE(lm3697_init_data),
+ .channel = lm3697_channel_data,
+ .mode = lm3697_mode_data,
+ .ramp = lm3697_ramp_data,
+ .ramp_reg_offset = 1, /* For LM3697_REG_BL1_RAMPUP/DN */
+ .enable = &lm3697_enable_reg,
+ .brightness_msb = lm3697_brightness_msb_regs,
+ .brightness_lsb = lm3697_brightness_lsb_regs,
+};
+
+static int lm3532_ramp_table[] = { 0, 1, 2, 4, 8, 16, 32, 65 };
+
+static int lm3631_ramp_table[] = {
+ 0, 1, 2, 5, 10, 20, 50, 100,
+ 250, 500, 750, 1000, 1500, 2000, 3000, 4000,
+};
+
+static int common_ramp_table[] = {
+ 2, 250, 500, 1000, 2000, 4000, 8000, 16000,
+};
+
+#define LM3532_MAX_CHANNELS 3
+#define LM3631_MAX_CHANNELS 2
+#define LM3632_MAX_CHANNELS 2
+#define LM3633_MAX_CHANNELS 3
+#define LM3695_MAX_CHANNELS 2
+#define LM3697_MAX_CHANNELS 3
+
+const struct ti_lmu_bl_cfg lmu_bl_cfg[LMU_MAX_ID] = {
+ {
+ .reginfo = &lm3532_reg_info,
+ .num_channels = LM3532_MAX_CHANNELS,
+ .max_brightness = MAX_BRIGHTNESS_8BIT,
+ .pwm_action = UPDATE_PWM_AND_BRT_REGISTER,
+ .ramp_table = lm3532_ramp_table,
+ .size_ramp = ARRAY_SIZE(lm3532_ramp_table),
+ },
+ {
+ .reginfo = &lm3631_reg_info,
+ .num_channels = LM3631_MAX_CHANNELS,
+ .max_brightness = MAX_BRIGHTNESS_11BIT,
+ .pwm_action = UPDATE_PWM_ONLY,
+ .ramp_table = lm3631_ramp_table,
+ .size_ramp = ARRAY_SIZE(lm3631_ramp_table),
+ },
+ {
+ .reginfo = &lm3632_reg_info,
+ .num_channels = LM3632_MAX_CHANNELS,
+ .max_brightness = MAX_BRIGHTNESS_11BIT,
+ .pwm_action = UPDATE_PWM_ONLY,
+ },
+ {
+ .reginfo = &lm3633_reg_info,
+ .num_channels = LM3633_MAX_CHANNELS,
+ .max_brightness = MAX_BRIGHTNESS_11BIT,
+ .pwm_action = UPDATE_MAX_BRT,
+ .ramp_table = common_ramp_table,
+ .size_ramp = ARRAY_SIZE(common_ramp_table),
+ .fault_monitor_used = true,
+ },
+ {
+ .reginfo = &lm3695_reg_info,
+ .num_channels = LM3695_MAX_CHANNELS,
+ .max_brightness = MAX_BRIGHTNESS_11BIT,
+ .pwm_action = UPDATE_PWM_AND_BRT_REGISTER,
+ },
+ {
+ .reginfo = &lm3697_reg_info,
+ .num_channels = LM3697_MAX_CHANNELS,
+ .max_brightness = MAX_BRIGHTNESS_11BIT,
+ .pwm_action = UPDATE_PWM_AND_BRT_REGISTER,
+ .ramp_table = common_ramp_table,
+ .size_ramp = ARRAY_SIZE(common_ramp_table),
+ .fault_monitor_used = true,
+ },
+};
diff --git a/drivers/video/backlight/ti-lmu-backlight-data.h b/drivers/video/backlight/ti-lmu-backlight-data.h
new file mode 100644
index 000000000000..c64e8e6513e1
--- /dev/null
+++ b/drivers/video/backlight/ti-lmu-backlight-data.h
@@ -0,0 +1,95 @@
+/*
+ * TI LMU (Lighting Management Unit) Backlight Device Data Definitions
+ *
+ * Copyright 2015 Texas Instruments
+ *
+ * Author: Milo Kim <milo.kim@xxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __TI_LMU_BACKLIGHT_H__
+#define __TI_LMU_BACKLIGHT_H__
+
+#include <linux/mfd/ti-lmu.h>
+#include <linux/mfd/ti-lmu-register.h>
+
+#define MAX_BRIGHTNESS_8BIT 255
+#define MAX_BRIGHTNESS_11BIT 2047
+
+enum ti_lmu_bl_pwm_action {
+ /* Update PWM duty, no brightness register update is required */
+ UPDATE_PWM_ONLY,
+ /* Update not only duty but also brightness register */
+ UPDATE_PWM_AND_BRT_REGISTER,
+ /* Update max value in brightness registers */
+ UPDATE_MAX_BRT,
+};
+
+struct lmu_bl_reg_data {
+ u8 reg;
+ u8 mask;
+ u8 val;
+};
+
+/**
+ * struct ti_lmu_bl_reg
+ *
+ * @init: Device initialization registers
+ * @num_init: Numbers of initialization registers
+ * @channel: Backlight channel configuration registers
+ * @mode: Brightness control mode registers
+ * @ramp: Ramp registers for lighting effect
+ * @ramp_reg_offset: Ramp register offset.
+ * Only used for multiple ramp registers.
+ * @enable: Enable control register address
+ * @enable_usec: Delay time for updating enable register.
+ * Unit is microsecond.
+ * @brightness_msb: Brightness MSB(Upper 8 bits) registers.
+ * Concatenated with LSB in 11 bit dimming mode.
+ * In 8 bit dimming, only MSB is used.
+ * @brightness_lsb: Brightness LSB(Lower 3 bits) registers.
+ * Only valid in 11 bit dimming mode.
+ */
+struct ti_lmu_bl_reg {
+ const struct lmu_bl_reg_data *init;
+ int num_init;
+ const struct lmu_bl_reg_data *channel;
+ const struct lmu_bl_reg_data *mode;
+ const struct lmu_bl_reg_data *ramp;
+ int ramp_reg_offset;
+ u8 *enable;
+ unsigned long enable_usec;
+ u8 *brightness_msb;
+ u8 *brightness_lsb;
+};
+
+/**
+ * struct ti_lmu_bl_cfg
+ *
+ * @reginfo: Device register configuration
+ * @num_channels: Number of backlight channels
+ * @max_brightness: Max brightness value of backlight device
+ * @pwm_action: How to control brightness registers in PWM mode
+ * @ramp_table: [Optional] Ramp time table for lighting effect.
+ * It's used for searching approximate register index.
+ * @size_ramp: [Optional] Size of ramp table
+ * @fault_monitor_used: [Optional] Set true if the device needs to handle
+ * LMU fault monitor event.
+ *
+ * This structure is used for device specific data configuration.
+ */
+struct ti_lmu_bl_cfg {
+ const struct ti_lmu_bl_reg *reginfo;
+ int num_channels;
+ int max_brightness;
+ enum ti_lmu_bl_pwm_action pwm_action;
+ int *ramp_table;
+ int size_ramp;
+ bool fault_monitor_used;
+};
+
+extern const struct ti_lmu_bl_cfg lmu_bl_cfg[LMU_MAX_ID];
+#endif